PTL 1 discloses a wireless communication device including a plurality of antennas. In the wireless communication device disclosed in PTL 1, two conductor plates are disposed between two antennas, and a slit is formed by providing short-circuit members at two locations between the two conductor plates. The wireless communication device disclosed in PTL 1 is configured such that the slit has a function equivalent to a slit antenna to improve isolation between two antennas.